P470 Comparative effectiveness analysis of flares, hospitalisations, and corticosteroid use among biologic naïve patients with inflammatory bowel disease within 12 months of initiation of vedolizumab or infliximab

Abstract

Background: This study aimed to compare IBD-related flare, hospitalisations, and corticosteroid use within one year of initiation of vedolizumab (VDZ) versus infliximab (IFX) among biologic-naïve IBD patients in a real-world setting. Methods: We undertook retrospective analysis of data from 01/05/2014 to 27/07/2016 in the US Explorys Universe electronic medical records database. Inclusion criteria included: diagnosis with UC (ICD-9 556.xx) or CD (ICD-9 555.xx); initiation of VDZ or IFX as 1st-line biologic therapy; age ≥18 years; ≥12 months of medical history, and; ≥12 months of follow-up. Patients commencing concomitant biologic therapies were excluded. Propensity scores were used to match VDZ initiators to IFX initiators (1:2). IBD-related flare was defined as ≥1 of: prescription for IV corticosteroids; IBD-related hospitalization; or IBD-related surgery. The percentage of patients experiencing ≥1 flare in the first 12 months of follow-up was reported, with focus on the proportion of patients admitted for an IBD-related hospitalization (and annual rate). The proportion of patients who received ≥1 oral/IV/rectal corticosteroid prescription, during induction (0–98 days follow-up), and post-induction (99–365 days follow-up) were also reported. Results: 81 VDZ initiators were matched to 162 IFX initiators. Among VDZ patients, median age was 44 years (interquartile range, IQR: 30, 56), 63.0% (n=51) had CD, 51.9% (n=42) were female, and median time since diagnosis was 3.6 years (IQR: 1.2, 6.2). No significant differences were observed in baseline characteristics between VDZ and IFX patients. Within 12 months of treatment initiation, 30.9% (95% CI: 21.9, 41.6) VDZ and 31.5% (95% CI: 24.8, 39.0) IFX patients experienced flare. In particular, 12.3% (95% CI: 6.8, 21.3) of the VDZ patients experienced IBD-related hospitalisation, and the associated annual rate was 0.2 (95% CI: 0.1, 0.4); among IFX patients the percentage was 17.9% (95% CI: 12.8, 24.5), and annual rate 0.4 (95% CI: 0.3. 0.5). During induction 28.4% (95% CI: 19.7, 39.0) VDZ patients and 33.3% (95% CI: 26.5, 40.9) IFX patients were treated with corticosteroids; during maintenance these proportions were 35.8% (95% CI: 26.2, 46.7) and 39.5% (95% CI: 32.3, 47.2), respectively. Conclusions: In a real-world setting, within one year of biologic treatment initiation, IBD patients receiving VDZ as 1st-line biologic therapy experienced numerically lower rates of flares compared with IFX. Similarly, a smaller proportion of VDZ patients experienced hospitalisation or received steroid treatment. Further studies in larger cohorts are required to confirm these trends.